Which element is in the lanthanide family?

Which Element Is In The Lanthanide Family?

Answers

Answer 1

Answer:

The 15 elements, together with their chemical symbols, are lanthanum (La)

Answer 2

Answer:

PM Promethium

Explanation:


Related Questions

In a food chain, energy does NOT flow directly from - F producer to decomposer G producer to consumer H consumer to decomposer J consumer to producer

Answers

Answer:

producer to decomposer

Explanation:

This is because in a food chain , energy flow from one trophic level to another. The producer which include plants are the source of energy which they manufacture good in the presence of light energy from sun. Energy flow directly from the producer to the primary consumer which are heterotrophs that feed on plants. Energy flow from consumer to decomposer after the consumer died and it is decayed.

Which of the following explanations accounts for the fact that the ion-solvent interaction is greater for Li+ than for K+?
The ionization energy of Li is higher than that for K.
Li has a lower density than K.
Li+ is of a lower mass than K+
Li+has a smaller ionic radius than K+
Li reacts with water more slowly than K.

Answers

The most appropriate explanation among the given options for the fact that the ion-solvent interaction is greater for Li⁺ than for K⁺ is that "Li⁺ has a smaller ionic radius than K⁺." Option D is correct.

Ionic radius refers to the size of an ion, specifically the distance between the nucleus and the outermost electron shell. Smaller ions tend to have stronger interactions with solvent molecules because the charge is more concentrated in a smaller space, leading to a higher electrostatic attraction between the ion and the surrounding solvent molecules.

In this case, Li⁺ has a smaller ionic radius compared to K⁺. As a result, Li⁺ has a stronger interaction with the solvent molecules, which leads to a greater ion-solvent interaction.

Hence, D. is the correct option.

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--The given question is incomplete, the complete question is

"Which of the following explanations accounts for the fact that the ion-solvent interaction is greater for Li⁺ than for K⁺? A) The ionization energy of Li is higher than that for K. B) Li has a lower density than K. C) Li⁺ is of a lower mass than K⁺ D) Li⁺ has a smaller ionic radius than K⁺ E) Li reacts with water more slowly than K."--

I need help on this question

Answers

Answer:

I only

last answer

Explanation:

When H+ forms a Bond with H2O to form the Hydronium ion H3 plus this bond is called a coordinate covalent bond because

Answers

Answer:

Because both the bonding electrons come from the oxygen atom. Explanation: A coordinate covalent bond is formed when both the bonding electrons are coming from the same atom

Explanation:

What would it mean if a forecaster claimed, “There will be east winds of 25 to 30 mph

Answers

Answer:

there will be winds moving from 25miles per hour to 30 miles per hour towards the east

To remove a tight-fitting lid from a jar, Megan runs the lid under hot water.
What happens to the Jar lid when its temperature increases?
A.The temperature increases, and the lid expands
B.The temperature decreases, and the lid contracts.
C.The potential energy increases, and the lid contracts.
D.The potential energy decreases, and the lid expands

Answers

the answer is A

step by step explanation

Answer:

A

Explanation:

which set of elements is arranged in order of increasing electronegativity? A. cl < f < se < as B. se < f < as < cl C. f < cl < se < as D. as < se < cl < f

Answers

f < cl < se < as (fluorine, chlorine, selenium, arsenic), which arranges the elements in increasing order of electronegativity.

Hence, the correct option is C.

Electronegativity is a measure of an atom's ability to attract electrons towards itself when it is part of a chemical bond. It generally increases as you move across a period from left to right and decreases as you move down a group in the periodic table.

A. cl < f < se < as (chlorine, fluorine, selenium, arsenic):

Chlorine (Cl) has a higher electronegativity than fluorine (F), selenium (Se), and arsenic (As). Therefore, it is arranged correctly that chlorine has the highest electronegativity, followed by fluorine, selenium, and then arsenic.

B. se < f < as < cl (selenium, fluorine, arsenic, chlorine):

This arrangement is not in increasing order of electronegativity. Fluorine (F) has the highest electronegativity among these elements, followed by chlorine (Cl), then arsenic (As), and selenium (Se) has the lowest electronegativity.

C. f < cl < se < as (fluorine, chlorine, selenium, arsenic):

This arrangement is correct. Fluorine (F) has the highest electronegativity, followed by chlorine (Cl), then selenium (Se), and arsenic (As) has the lowest electronegativity.

D. as < se < cl < f (arsenic, selenium, chlorine, fluorine):

This arrangement is not in increasing order of electronegativity. Fluorine (F) has the highest electronegativity among these elements, followed by chlorine (Cl), then selenium (Se), and arsenic (As) has the lowest electronegativity.

Therefore, the correct answer is option C: f < cl < se < as (fluorine, chlorine, selenium, arsenic), which arranges the elements in increasing order of electronegativity.

Hence, the correct option is C.

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fire heats up a pot → pot cooks food → food fuels body → body releases heat during activity where is energy created in this energy chain?

Answers

In the given energy chain, the energy is created in the fire when it heats up the pot. When the pot heats up, it cooks the food that fuels the body. As the food fuels the body, the body releases heat during activity. Therefore, the energy is created in the initial stage of the chain, i.e., when the fire heats up the pot.

The given energy chain is as follows:

Fire heats up a pot → Pot cooks food → Food fuels body → Body releases heat during activity

In the given energy chain, the energy is created in the first step when the fire heats up the pot. As the fire heats up the pot, the pot becomes hot and cooks the food that is in it. This cooking of food releases energy, which can be used by the body.The energy is then transferred to the body as it consumes the cooked food. The food fuels the body and provides it with the necessary energy to carry out activities. As the body uses this energy, it also releases heat during activity, which can be measured in the form of sweat or an increase in body temperature.Therefore, the energy is created in the fire heats up the pot step of the energy chain.

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here is a more complex redox reaction involving the permanganate ion in acidic solution: 5no2− 6h 2mno4− → 5no3− 2mn2 3h2o

Answers

The balanced equation of the redox reaction is:5NO2−+ 6H+ + 2MnO4− → 5NO3− + 2Mn2+ + 3H2O.

Redox reaction involving the permanganate ion in acidic solution:5NO2−+ 6H+ + 2MnO4− → 5NO3− + 2Mn2+ + 3H2OThe balanced redox reaction that involves the permanganate ion in acidic solution is given by:5NO2−+ 6H+ + 2MnO4− → 5NO3− + 2Mn2+ + 3H2OFor balancing the given reaction in acidic solution, we follow the given steps:Step 1: Writing the unbalanced reaction in the ionic form:Step 2: Separating the half-reactions for oxidation and reduction:Oxidation half-reaction: 5NO2− → 5NO3−Reduction half-reaction: 2MnO4− → 2Mn2+Step 3: Balancing the number of atoms of elements in half-reactionsBalancing oxidation half-reaction:5NO2− → 5NO3− + 10H+ + 2e-Balancing reduction half-reaction: 16H+ + 2MnO4− → 2Mn2+ + 8H2O + 5e-Step 4: Balancing the number of electrons lost and gained in each half-reaction by multiplying by a coefficient.Oxidation half-reaction: 5NO2− → 5NO3− + 10H+ + 2e-Balancing reduction half-reaction: 16H+ + 2MnO4− → 2Mn2+ + 8H2O + 5e-Now, the electrons lost and gained are balanced.Step 5: Balancing the number of hydrogen ions in each half-reaction:Oxidation half-reaction: 5NO2− + 10H+ → 5NO3− + 2e-Balancing reduction half-reaction: 2MnO4− + 16H+ → 2Mn2+ + 8H2O + 5e-Step 6: Balancing the number of oxygen atoms in each half-reaction by adding H2O molecules to the side that needs it. For acidic solution, add H+ ions to balance the oxygen atoms.Oxidation half-reaction: 5NO2− + 10H+ → 5NO3− + 2e-Balancing reduction half-reaction: 2MnO4− + 16H+ → 2Mn2+ + 8H2O + 5e-Now, the number of oxygen atoms is balanced.Step 7: Adding half-reactions, multiplying by integers (if necessary) to equalize the electrons in each half-reaction, and canceling species common to both sides.5NO2− + 2MnO4− + 16H+ → 5NO3− + 2Mn2+ + 8H2OFinally, the balanced equation of the redox reaction is:5NO2−+ 6H+ + 2MnO4− → 5NO3− + 2Mn2+ + 3H2O.

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cbr4 has a higher vapor pressure at the same temperature than ccl4. T/F?

Answers

CBr₄ has a higher vapor pressure at the same temperature than CCl₄. The statement is False.

The vapor pressure of a liquid is the pressure exerted by the vapor of the liquid in equilibrium with the liquid. The vapor pressure of a liquid depends on the strength of the intermolecular forces in the liquid. The stronger the intermolecular forces, the lower the vapor pressure.

In the case of CCl₄ and CBr₄, the intermolecular forces are London dispersion forces. The size of the atom or molecule affects the strength of the London dispersion forces. The larger the atom or molecule, the stronger the London dispersion forces.

Bromine is larger than chlorine, so the intermolecular forces in CBr₄ are stronger than the intermolecular forces in CCl₄. Therefore, CCl₄ will have a higher vapor pressure than CBr₄ at the same temperature.

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it takes 45 hours for a 6.00 mg sample of sodium-24 to decay to 0.750 mg. what is the half-life of sodium-24?

Answers

To find the half-life of sodium-24, we can use the formula for exponential decay:

N(t) = N₀ * (1/2)^(t / t₁/₂)

Where:

N(t) is the amount of the substance remaining at time t

N₀ is the initial amount of the substance

t is the time elapsed

t₁/₂ is the half-life of the substance

Given:

N₀ = 6.00 mg (initial amount)

N(t) = 0.750 mg (amount after 45 hours)

Plugging in these values, we can solve for t₁/₂:

0.750 mg = 6.00 mg * (1/2)^(45 / t₁/₂)

Dividing both sides of the equation by 6.00 mg:

(0.750 mg) / (6.00 mg) = (1/2)^(45 / t₁/₂)

0.125 = (1/2)^(45 / t₁/₂)

To eliminate the base of 1/2, we can take the logarithm of both sides:

log₂(0.125) = 45 / t₁/₂ * log₂(1/2)

Using the property log₂(a^b) = b * log₂(a):

log₂(0.125) = 45 * log₂(1/2) / t₁/₂

We know that log₂(1/2) = -1, so we can simplify the equation further:

log₂(0.125) = -45 / t₁/₂

Now, we can solve for t₁/₂:

t₁/₂ = -45 / log₂(0.125)

Using a calculator:

t₁/₂ ≈ -45 / (-3) ≈ 15

The half-life of sodium-24 is approximately 15 hours.

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What is the mass of sulfuric acid, h2so4, that is contained in 2.0L of a 5.85 M solution ?
A- 1147.44 grams
B- 0.12 grams
C- 11.7 grams
D- 98.07 grams

Answers

Answer:

A. 1147.44 grams

Explanation:

Multiply volume by molarity to get the moles of solution.

5.85 M = mol/2.0 L

mol = (5.85 M)(2.0 L)

mol = 11.7

There is 11.7 moles of H2SO4.

Convert to grams with molar mass.

11.7 mol H2SO4 x (98.076 g/1 mol) = 1147.49 g

Closest answer is A, 1147.44 g.

If the concentration of OH in a saturated solution of Ca(OH)₂ is 5.2 x 10-² M, is the solubility of Ca(OH)2 greater than 0.1g/100.mL? (Molar mass of Ca(OH)2 is 74.1 g/mol) a. Same b. No C. Yes

Answers

Comparing the calculated solubility of Ca(OH)₂ (1.924 g/100 mL) to the given value of 0.1 g/100 mL, we can conclude that the solubility of Ca(OH)₂ is greater than 0.1 g/100 mL.

Option (c) is correct.

To determine if the solubility of Ca(OH)₂ is greater than 0.1 g/100 mL based on the given concentration of OH⁻, we need to calculate the solubility of Ca(OH)₂ using the provided concentration.

The balanced chemical equation for the dissociation of Ca(OH)₂ is:

Ca(OH)₂ ⇌ Ca²⁺ + 2OH⁻

From the equation, we can see that for every mole of Ca(OH)₂ that dissolves, two moles of OH⁻ ions are produced. Therefore, the concentration of OH⁻ is twice the concentration of Ca(OH)₂.

Given that the concentration of OH⁻ is 5.2 x 10⁻² M, the concentration of Ca(OH)₂ can be calculated by dividing the concentration of OH⁻ by 2:

Ca(OH)₂ concentration = (5.2 x 10⁻² M) / 2 = 2.6 x 10⁻² M

To determine the solubility of Ca(OH)₂ in grams per 100 mL, we can use the molar mass of Ca(OH)₂:

Solubility of Ca(OH)₂ = (2.6 x 10⁻² M) x (74.1 g/mol) = 1.924 g/100 mL

Comparing the calculated solubility of Ca(OH)₂ (1.924 g/100 mL) to the given value of 0.1 g/100 mL, we can conclude that the solubility of Ca(OH)₂ is greater than 0.1 g/100 mL.

Therefore, the correct answer is c) Yes.

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consider the effect of a volume change on this reaction at equilibrium. 2h2s(g)⇌2h2(g) s2(g)
Predict the effect (shift right, shift left, or no effect) of increasing the reaction volume.

Answers

For the reaction 2H2S(g) ⇌ 2H2(g) + S2(g), the effect of a volume change on this reaction at equilibrium can be considered. It can be predicted whether increasing the reaction volume will cause the reaction to shift to the right, shift to the left, or have no effect on the reaction.

In this reaction, two moles of gaseous reactants are being converted into two moles of gaseous products. Therefore, this is a reaction that involves a change in volume. According to Le Chatelier's principle, the equilibrium will shift in such a way as to counteract the effect of the volume change.

If the reaction volume is increased by adding inert gas (i.e., a gas that doesn't react with the reactants), then the total pressure of the system will increase, but the partial pressures of the reactants and products will remain the same. Since the partial pressures remain unchanged, the equilibrium will not shift in either direction.

However, if the reaction volume is decreased by removing some of the gaseous products, then the partial pressure of the products will decrease. In order to counteract this decrease, the equilibrium will shift to the right to produce more gaseous products (i.e., more H2 and S2). Therefore, decreasing the volume will cause the reaction to shift to the right.

Therefore, increasing the reaction volume will have no effect on this reaction at equilibrium.

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Describe the acid-base behavior of amphiproti substances Question Choose the options below that are amphiprotic, Select all that apply: a. H2SO4 b. HS- c. PO43- d. NH3

Answers

The amphiprotic substances among the options provided are HS⁻ and NH₃.

The term "amphiprotic" refers to substances that can act as both acids and bases, depending on the reaction conditions.

a. H₂SO₄ (sulfuric acid) is not considered amphiprotic. It is a strong acid that readily donates a proton (H+) but does not accept protons in typical acid-base reactions.

b. HS⁻ (hydrogen sulfide ion) is amphiprotic. It can act as a base by accepting a proton to form H₂S (hydrogen sulfide), and it can also act as an acid by donating a proton to form S²⁻ (sulfide ion).

c. PO₄³⁻ (phosphate ion) is not considered amphiprotic. It is a polyprotic base that can donate multiple protons, but it does not accept protons in typical acid-base reactions.

d. NH₃ (ammonia) is amphiprotic. It acts as a base by accepting a proton to form NH₄⁺ (ammonium ion), and it can also act as an acid by donating a proton to form NH₂⁻ (amide ion).

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For practice, the molecular formula for ascorbic acid is C6H8O6, and you used 6 g in this experiment, calculate the molarity of the ascorbic acid. Now calculate the concentration in moles per drop (assume 1 mL = 20 drops).
I do not want the answer. I want to know how to get the answer please. Just explain to me how to figure this out.

Answers

Answer:

0.68 M

Explanation:

The concentration of a solute refers to Molarity= [tex]\frac{moles}{Liter}[/tex]

We need to find moles, we can do that by using stoichiometry to convert 6g > moles using molar mass.

Molar mass of C6H8O6= 176 g/mol; this is our key to converting the amount we have to moles.

6g C6H8O6 x [tex]\frac{1 mol}{176 g}[/tex]C6H8O6 = 0.034 mol C6H8O6

Now we need our volume per drop.

We know 1000 mL=1 L

We have 20 drops per 1 mL, so 1 mL / 20 = 0.05 mL per drop. But we need Liters, so we'll convert it to Liters.

0.05 mL x [tex]\frac{1 L}{1000mL}[/tex] = 0.00005L

Now we can solve for Molarity.

Molarity of C6H8O6 = [tex]\frac{0.034 mols}{0.00005 L}[/tex] = 0.068M of C6H8O6

Calculate the mass in grams of 8.35 × 10²² molecules of CBr₄.

Answers

To calculate the mass in grams of 8.35 × 10²² molecules of CBr₄ (carbon tetrabromide), we need to use Avogadro's number to convert the given number of molecules to moles and then use the molar mass of CBr₄ to convert moles to grams.

The molar mass of CBr₄ can be calculated by adding up the atomic masses of carbon (C) and four bromine (Br) atoms. The atomic mass of carbon is approximately 12.01 g/mol, and the atomic mass of bromine is approximately 79.90 g/mol.

Molar mass of CBr₄ = (1 × 12.01 g/mol) + (4 × 79.90 g/mol) = 331.74 g/mol

To convert the number of molecules to moles, we divide the given number of molecules by Avogadro's number (6.022 × 10²³ molecules/mol):

Moles of CBr₄ = (8.35 × 10²² molecules) / (6.022 × 10²³ molecules/mol) = 0.138 mol

Finally, to find the mass in grams, we multiply the number of moles by the molar mass:

Mass of CBr₄ = (0.138 mol) × (331.74 g/mol) = 45.80 g

Therefore, the mass in grams of 8.35 × 10²² molecules of CBr₄ is approximately 45.80 grams.

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Mass = 22g Volume = 2cm3 What is the Density?​

Answers

Answer:

11g/cm^3

Explanation:

The density of a substance can be found By

density= Mass/volume

From the question

mass = 22 g

volume = 2 cm³

22/2=11

We have the final answer as

11 g/cm³

Answer:

11g/cm^3

Explanation:

It is because the constant formula density is

Density=Mass/ Volume.

Therefore we have

Density=22g/2cm^3

Which is = 11g/cm^3

Shaun's doctor has recommended that he consume 200 calories of protein a day. Shaun consumed 176 calories of protein in one day. How much more protein does he need to consume to reach the required amount? (1 gram of protein = 4 calories)

Answers

Answer:  Shaun must consume 6 more g of protein to reach the required amount.

Explanation:

Given : Recommended amount of protein = 200 calories

Now 4 calories = 1 gram of protein

Thus 200 calories = [tex]\frac{1}{4}\times 200=50[/tex] g of protein.

Calories consumed per day by Shaun = 176 calories

176 calories =  [tex]\frac{1}{4}\times 176=44[/tex] g of protein.

Thus Shaun need to consume = (50-44) g = 6 of protein to reach the required amount.

Shaun must consume 6 more g of protein to reach the required amount.

help? for me? yes? please?

Answers

Answer:

2 Mg + O2 -> 2 MgO

is a synthesis reaction.

if i have 340 ml of a 0.5 m nabr solution, what will the concentration be if i add 500 ml more water to it?

Answers

The final concentration of the solution is determined as 0.59 M.

What is the final concentration of the solution?

The concentration of a solution or molarity of a solution is defined as the ratio of number of moles of solute to the liters of the solution.

Molarity, M = n / V

where;

n is the number of moles of the soluteV is the volume of the solution

The final concentration of the solution is calculated as follows;

the number of moles = 0.5 m

the total volume after adding 500 ml of water = 340 ml + 500 ml = 840 ml = 0.84 L

Molarity = 0.5 m / 0.84 L

Molarity = 0.59 M

Thus, the final concentration of the solution is determined as 0.59 M.

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.(Part A)
Write balanced net ionic equation for the following reaction:
Fe(OH)3(s)+H2SO4(aq)→?
Express your answer as a chemical equation. Identify all of the phases in your answer.
(Part B)
Write balanced net ionic equation for the following reaction:
HClO3(aq)+Na(OH)(aq)→?
Note that HClO3 is a strong acid.
Express your answer as a chemical equation. Identify all of the phases in your answer.

Answers

Part A: [tex]Fe(OH)_{3} (s)[/tex] + 3H+(aq) → [tex]Fe^3+(aq)[/tex]+ [tex]3H_{2}O(l)[/tex](solid [tex]Fe(OH)_{2}[/tex] reacts with aqueous H+ to form [tex]Fe^3+[/tex] ions and water). Part B: H+(aq) + [tex]ClO_{3}^-[/tex](aq) + Na+(aq) +[tex]OH^-(aq)[/tex]→ Na+(aq) + [tex]ClO_{3}^-(aq)[/tex] + [tex]H_{2}O(l)[/tex](H+ reacts with [tex]OH^-[/tex] to form water in the presence of Na+ and [tex]ClO_{3}^-[/tex] ions).

Part A:

The balanced net ionic equation for the reaction between solid [tex]Fe(OH)_{3}[/tex] and aqueous [tex]H_{2}SO_{4}[/tex]is:

[tex]Fe(OH)_{3} (s)[/tex] + 3H+(aq) + [tex]3SO_{4}^2-(aq)[/tex] → [tex]Fe^3+(aq)[/tex] + [tex]3SO_{4}^2-(aq)[/tex] +[tex]3H_{2}O(l)[/tex].

In this reaction, the [tex]Fe(OH)_{3}[/tex] solid reacts with the H+ ions from [tex]H_{2}SO_{4}[/tex]to form[tex]Fe^3+[/tex] ions and water molecules. The sulfate ions [tex](SO_{4}^2-)[/tex]are spectator ions and do not participate in the net reaction. The phases are indicated by (s) for solid, (aq) for aqueous, and (l) for liquid.

Part B:

The balanced net ionic equation for the reaction between [tex]HClO_{3}(aq)[/tex] and NaOH(aq) is:

H+(aq) + [tex]ClO_{3}^-(aq)[/tex]+ Na+(aq) + [tex]OH^-(aq)[/tex] → Na+(aq) + [tex]ClO_{3}^-(aq)[/tex] + [tex]H_{2}O(l)[/tex].

Here, the H+ ion from [tex]HClO_{3}[/tex] reacts with the [tex]OH^-[/tex] ion from NaOH to form water molecules. Sodium ion (Na+) and chlorate ion ([tex]ClO_{3}^-[/tex]) are spectator ions. The phases are indicated by (aq) for aqueous and (l) for liquid.

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Question 4 (2 points)

Manganese-56 decays by beta emission and has a half life of 2.6 hours. If a sample

is analyzed and found to contain 6.25% parent isotopes and 93.75% daughter

isotopes, what must the age of the sample be?

Answers

Answer:

10.4 hours

Explanation:

Now from;

0.693/t1/2 = 2.303/t log (No/N)

t1/2= half life of the radioactive isotope

t = age of the radioactive isotope

No= Original amount of radioactive isotope

N= amount of radioactive isotope left after time t

Substituting values;

N = 0.0625No

0.693/2.6 = 2.303/t log (No/0.0625No)

0.693/2.6 = 2.303/t log (1/0.0625)

0.267 = 2.303/t * log 16

0.267 = 2.773/t

t = 2.773/0.267

t = 10.4 hours

Calculate the number of moles in 7.04 g of lead (II) nitrate, Pb(NO3)2
Can Someone help me covert this?!

Answers

Answer:

moles Pb(NO₃)₂ ≅ 0.0213 mole (three sig. figs.)

Explanation:

converting...

grams to moles => divide by formula weight

moles to grams => multiply by formula weight

for this problem ...

moles Pb(NO₃)₂ = 7.04g / 331.2g/mol = 0.021256 (calculator answer)

≅ 0.0213 mole (three sig. figs.)

Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore,  the number of moles in 7.04 g of lead (II) nitrate, Pb(NO₃)₂ is 0.0212moles.

What is mole?

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.

Mathematically,

mole =given mass ÷ molar mass

Molar mass of 1 mole of  Pb(NO₃)₂ = 331.2g/mol

given mass of Pb(NO₃)₂=7.04g

Substituting the values in above formula we get

moles of Pb(NO₃)₂ = 7.04g / 331.2g/mol

moles of Pb(NO₃)₂ = 0.0212moles

Therefore,  the number of moles in 7.04 g of lead (II) nitrate, Pb(NO₃)₂ is  0.0212moles.

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4. Identify What do scientists call a substance that forms during a chemical reaction?
5. Identify On what side of the equation are reactants found?

Answers

Answer:

4. Reactant

5. Left

I hope this helps ❤️❤️

What is a net ionic equation? A. An equation that shows only those particles involved in the reaction, and that is balanced for mass but not for charge B. An equation that shows only those particles involved in the reaction, and that is balanced for both mass and charge C. An equation that describes the flow of oxygen in a combustion reaction D. An equation that shows the cations as reactants and the anions as products

Answers

Answer:

B. An equation that shows only those particles involved in the reaction, and that is balanced for both mass and charge

Explanation:

A net ionic equation is a chemical equation that will only show the elements, compounds, and ions that are directly involved in the chemical reaction. It comes from the balanced molecular equation and should be balanced by both mass and charge.

True or false? Lymph vessels pick up a little bit of fluid that leaves your blood vessels every time you heart pumps.

Answers

Answer:

Explanation:

true.                        

Answer:

True. why?

Because the fluid that is lost through the blood vessels is restored but with no central pump or heart, this device releases and collects fluid.

Given the balanced chemical equation: 2 H2 + O2 → 2 H20. Choose
the description below that most accurately describes the reaction.
O 2 moles of hydrogen react with 1 mole of oxygen to form 2 moles of water
O 2 moles of water react with 1 mole of hydrogen to form 2 moles of oxygen
O equal moles of hydrogen and oxygen react to form an equal amount of
water
O 4 moles of hydrogen react with 2 moles of oxygen to form 4 moles of water

Answers

Answer:

The answer is

2 moles of hydrogen react with 1 mole of oxygen to form 2 moles of water

What is the process of old crust sinking back into a mantle?

Answers

What is subduction? Subduction is the process which the ocean floor sinks beneath a deep-ocean trench and back into the mantle. (A process by which part of Earth's crust sinks downwards).

Newton's third law of motion is summarized as the law of action-reaction. For every action, there is an equal but opposite reaction. Which example best illustrates the application of Newton's law of action-reaction? Choose all that apply.

Answers

Answer:

When we stand on the floor, we apply a force on the floor surface in the downward direction and in return the floor also exerts an upward and equal force on us.

Explanation:

Newton' third law is vey famous and it states that for each and every action, there applies an equal but opposite reaction. Thus the action force and the reaction force always acts on pairs. But they does not contribute to the motion of the object.

One such example that illustrates the action and reaction force from Newton's law is when we stand on the floor we exert a force on the floor surface in downward direction. The floor surface also exerts an opposite and equal force on us in the upward direction.

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